Lactone-modified hydroxyethyl (meth)acrylates represented by the following formula (I): ##STR2## wherein R is CH.sub.3 or H, and n is an integer of from 3 to 20, are useful as a part of acrylic monomers for paints. But when they are standed for a long period of time (e.g., one to three days) at about 20.degree. C., the high molecular weight moiety thereof becomes a paste-like state, and therefore, when used, they must be heated at, for example, 40.degree. to 50.degree. C. for homogenization.
The inventor extensively studied to overcome such drawback and reviewed various solvents for the lactone-modified hydroxyethyl (meth)acrylate of the formula (I) to improve the workability. Thus, he attained the invention.